Conventionally, there have been proposed various steam cookers for performing cooking by using steam. Examples of the steam cookers can be seen in Patent Publications 1 to 3. For example, Patent Publication 1 discloses a steam cooking apparatus that blows steam into a food tray. Patent Publication 2 discloses a heat cooking apparatus that supplies superheated steam into an cooking chamber or makes steam in the cooking chamber superheated steam by radiation heat. Patent Publication 3 discloses a heat cooking apparatus that supplies superheated steam to the whole cooking chamber and/or a portion in the vicinity of foods.
Patent Publication 1: JP-U 03-67902 (1991) (p. 4 to 6 in whole specification, FIGS. 1 to 3)
Patent Publication 2: JP-A 08-49854 (1996) (p. 2 to 3, FIGS. 1 to 8)
Patent Publication 3: JP-A 11-141881 (1999) (p. 3 to 5, FIGS. 1 to 3)